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[texts]Apical Growth in Roots of Marsilia quadrifolia and Equisetum Arvense (Volume 15) - Wm. M. Andrews
"Apical Growth in Roots of Marsilia quadrifolia and Equisetum Arvense" is an article from Botanical Gazette, Volume 15. View more articles from Botanical Gazette.View this article on JSTOR.View this article's JSTOR metadata.You may also retrieve all of this items metadata in JSON at the following URL: https://archive.org/metadata/jstor-2993373
Downloads: 23
[texts]The Career of Marinette (Volume 5) - Gladys M. Andrews
"The Career of Marinette" is an article from The Wisconsin Magazine of History, Volume 5. View more articles from The Wisconsin Magazine of History.View this article on JSTOR.View this article's JSTOR metadata.You may also retrieve all of this items metadata in JSON at the following URL: https://archive.org/metadata/jstor-4630392
Downloads: 16
[texts]Olonial Folkways - Charles M. Andrews

Keywords: Pure Science
Downloads: 75
Book digitized by Google and uploaded to the Internet Archive by user tpb.
Downloads: 125
[texts]The Fathers Of New England - Charles M. Andrews

Keywords: History
Downloads: 844
[texts]The Fathers Of New England - Charles M. Andrews

Keywords: History
Downloads: 243
[texts]Mid-Infrared and Submillimeter Observations of the Illuminating Source of McNeil's Variable Nebula - Sean M. Andrews
We present post-outburst observations of the mid-infrared spectrum and submillimeter continuum of the illuminating source of the newly-discovered McNeil's Nebula in the L1630 region of Orion. The 12 micron flux of this source has increased by a factor of 25 after the outburst, whereas the submillimeter continuum remains at its pre-outburst level. The bolometric luminosity has increased by at least an order of magnitude, to ~34 L_sun, and is likely less than 90 L_sun...
Downloads: 14
[texts]Submillimeter studies of circumstellar disks in Taurus and Orion - Jonathan P. Williams
We highlight two recent studies of circumstellar disks in the Taurus and Orion star forming regions. Using the JCMT and CSO, we measure disk fluxes in Taurus over a wide range of submillimeter wavelengths and determine the frequency dependence of the dust opacity. We find clear evidence for a systematic change in its behavior with time, most readily explained by grain growth. Using the SMA, we observed the protoplanetary disks (proplyds) in the Orion Trapezium cluster...
Downloads: 3
[texts]A Submillimeter View of Circumstellar Dust Disks in $ρ$ Ophiuchus - Sean M. Andrews
We present new multiwavelength submillimeter continuum measurements of the circumstellar dust around 48 young stars in the $\rho$ Ophiuchus dark clouds. Supplemented with previous 1.3 mm observations of an additional 99 objects from the literature, the statistical distributions of disk masses and submillimeter colors are calculated and compared to those in the Taurus-Auriga region. These basic submillimeter properties of young stellar objects in both environments are shown to be essentially iden...
Downloads: 3
[texts]The LkHa 101 Cluster - Sean M. Andrews
In the infrared, the heavily reddened LkH$\alpha$ 101 is one of the brightest young stars in the sky. Situated just north of the Taurus-Auriga complex in the L1482 dark cloud, it appears to be an early B-type star that has been serendipitously exposed during a rarely observed stage of early evolution, revealing a remarkable spectrum and a directly-imaged circumstellar disk. While detailed studies of this star and its circumstellar environment have become increasingly sophisticated in the 50 year...
Downloads: 7
[texts]The Dust Properties of Eight Debris Disk Candidates as Determined by Submillimeter Photometry - Jonathan P. Williams
The nature of far-infrared dust emission toward main sequence stars, whether interstellar or circumstellar, can be deduced from submillimeter photometry. We present JCMT/SCUBA flux measurements at 850 microns toward 8 stars with large photospheric excesses at 60-100 microns. 5 sources were detected at 3-sigma or greater significance and one was marginally detected at 2.5-sigma. The inferred dust masses and temperatures range from 0.033 to 0.24 Earth masses and 43-65 K respectively...
Downloads: 4
[texts]Circumstellar Dust Disks in Taurus-Auriga: The Submillimeter Perspective - Sean M. Andrews
We present a sensitive, multiwavelength submillimeter continuum survey of 153 young stellar objects in the Taurus-Auriga star formation region. The submillimeter detection rate is 61% to a completeness limit of ~10 mJy (3-sigma) at 850 microns. The inferred circumstellar disk masses are log-normally distributed with a mean mass of ~0.005 solar masses and a large dispersion (0.5 dex). Roughly one third of the submillimeter sources have disk masses larger than the minimal nebula from which the sol...
Downloads: 5
[texts]High Resolution Submillimeter Constraints on Circumstellar Disk Structure - Sean M. Andrews
We present a high spatial resolution submillimeter continuum survey of 24 circumstellar disks in the Tau-Aur and Oph-Sco star formation regions using the SMA. In the context of a simple model, we use broadband SEDs and submillimeter visibilities to derive constraints on some basic parameters that describe the structure of these disks. For the typical disk in the sample we infer a radial surface density distribution \Sigma ~ r^-p with a median p ~ 0.5, although consideration of the systematic eff...
Downloads: 1
[texts]Submillimeter Array Observations of Disks in the SR 24 Multiple Star System - Sean M. Andrews
We present high-resolution aperture synthesis images from the Submillimeter Array of the 225 GHz (1.3 mm) continuum and CO J=2-1 line emission from the disks around components of the hierarchical triple system SR 24, located in the Ophiuchus star-forming region. The most widely separated component, SR 24 S (with a projected semimajor axis of 832 AU), has a circumstellar disk with properties typical of those around single T Tauri stars...
Downloads: 4
[texts]Small-Scale Interstellar Na I Structure Toward M92 - Sean M. Andrews
We have used integral field echelle spectroscopy with the DensePak fiber-optic array on the KPNO WIYN telescope to observe the central 27" x 43" of the globular cluster M92 in the Na I D wavelength region at a spatial resolution of 4". Two interstellar Na I absorption components are evident in the spectra at LSR velocities of 0 km/s (Cloud 1) and -19 km/s (Cloud 2). Substantial strength variations in both components are apparent down to scales limited by the fiber-to-fiber separations...
Downloads: 3
[texts]Report of the Trial of Samuel M. Andrews: Including the Rulings of the Court Upon Many Questions ... - Samuel M. Andrews , Charles Gideon Davis , Massachusetts Supreme judicial court
Book digitized by Google from the library of Harvard University and uploaded to the Internet Archive by user tpb.
Downloads: 93
[texts]Millimeter Imaging of the beta Pictoris Debris Disk: Evidence for a Planetesimal Belt - David J. Wilner
We present observations at 1.3 millimeters wavelength of the beta Pictoris debris disk with beam size 4.3 x 2.6 arcsec (83 x 50 AU) from the Submillimeter Array. The emission shows two peaks separated by ~7 arsec along the disk plane, which we interpret as a highly inclined dust ring or belt. A simple model constrains the belt center to 94+/-8 AU, close to the prominent break in slope of the optical scattered light...
Downloads: 7
[texts]The Masses of the Orion Proplyds from Submillimeter Dust Emission - Jonathan P. Williams
We have imaged the 880 micron continuum emission from the "proplyds" in the center of the Trapezium Cluster in Orion using the Submillimeter Array with a beam size 1.5'' FWHM and an rms of 2.7 mJy. Five sources are detected with fluxes in the range 18 to 38 mJy, which includes dust emission from four proplyds and ionized gas from theta1 Ori G. The total masses of the detected proplyds derived from their dust emission range from 0.013 to 0.024 Msun assuming a dust temperature of 20 K and mass opa...
Downloads: 7
[texts]Millimeter Dust Emission in the GQ Lup System - Yu Dai
We present Submillimeter Array observations of the GQ Lup system at 1.3 millimeters wavelength with $0\farcs4$ ($\sim$60 AU) resolution. Emission is detected from the position of the primary star, GQ Lup A, and is marginally resolved. No emission is detected from the substellar companion, GQ Lup B, $0\farcs7$ away. These data, together with models of the spectral energy distribution, suggest a compact disk around GQ Lup A with mass $\sim 3$ M$_{Jup}$, perhaps truncated by tidal forces...
Downloads: 2
[texts]The Ionization Fraction in the DM Tau Protoplanetary Disk - Karin I. Oberg
We present millimeter-wave observations of several molecular ions in the disk around the pre-main-sequence star DM Tau and use these to investigate the ionization fraction in different regions of the disk. New Submillimeter Array (SMA) observations of H2D+ J=1_10 - 1_11, N2H+ J=4-3 and CO J=3-2 are presented. H2D+ and N2H+ are not detected and using the CO 3-2 disk size the observations result in an upper limit of 20 K where CO is in the gas-phase and HCO+ is most abundant, where we estimate xi ...
Downloads: 3
[texts]A Resolved Census of Millimeter Emission from Taurus Multiple Star Systems - Robert J. Harris
We present a high angular resolution millimeter-wave dust continuum imaging survey of circumstellar material associated with individual components of 23 multiple star systems in the Taurus-Auriga young cluster. Combined with previous measurements, these new data permit a comprehensive look at how millimeter luminosity (a tracer of disk mass) relates to the separation and mass of a stellar companion...
Downloads: 14
[texts]Truncated Disks in TW Hya Association Multiple Star Systems - Sean M. Andrews
We present high angular resolution (down to 0.3" = 13 AU in diameter) Submillimeter Array observations of the 880 micron (340 GHz) thermal continuum emission from circumstellar dust disks in the nearby HD 98800 and Hen 3-600 multiple star systems. In both cases, the dust emission is resolved and localized around one stellar component - the HD 98800 B and Hen 3-600 A spectroscopic binaries - with no evidence for circum-system material...
Downloads: 4
[texts]1899 wholesale offer of hardy cacti, rare Colorado conifers, novelties in shrubs and plants of the Rocky Mountain region (Volume 1899) - D.M. Andrews (Firm)
Cover title
Keywords: Nurseries (Horticulture) Colorado Boulder Catalogs; Nursery stock Colorado Boulder Catalogs; Plants Rocky Mountains Catalogs; Cactus Rocky Mountains Catalogs; Flowers Seeds Rocky Mountains Catalogs; Shrubs Rocky Mountains Catalogs; Conifers Rocky Mo
Downloads: 3
[texts]Protoplanetary Disk Structures in Ophiuchus II: Extension to Fainter Sources - Sean M. Andrews
We present new results from a significant extension of our previous high angular resolution (0.3" = 40 AU) Submillimeter Array survey of the 880 um continuum emission from dusty circumstellar disks in the ~1 Myr-old Ophiuchus star-forming region. An expanded sample is constructed to probe disk structures that emit significantly lower millimeter luminosities (hence dust masses), down to the median value for T Tauri stars...
Downloads: 12
[texts]Matryoshka Holes: Nested Emission Rings in the Transitional Disk Oph IRS 48 - Joanna M. Brown
The processes that form transition disks - disks with depleted inner regions - are not well understood; possible scenarios include planet formation, grain growth and photoevaporation. Disks with spatially resolved dust holes are rare, but, in general, even less is known about the gas structure. The disk surrounding A0 star Oph IRS 48 in the nearby Rho Ophiuchus region has a 30 AU radius hole previously detected in the 18.7 micron dust continuum and in warm CO in the 5 micron fundamental ro-vibra...
Downloads: 2
[texts]Empirical Constraints on Turbulence in Protoplanetary Accretion Disks - A. Meredith Hughes
We present arcsecond-scale Submillimeter Array observations of the CO(3-2) line emission from the disks around the young stars HD 163296 and TW Hya at a spectral resolution of 44 m/s. These observations probe below the ~100 m/s turbulent linewidth inferred from lower-resolution observations, and allow us to place constraints on the turbulent linewidth in the disk atmospheres. We reproduce the observed CO(3-2) emission using two physical models of disk structure: (1) a power-law temperature distr...
Downloads: 2
[texts]A Closer Look at the LkCa 15 Protoplanetary Disk - Sean M. Andrews
We present 870 micron observations of dust continuum emission from the LkCa 15 protoplanetary disk at high angular resolution (with a characteristic scale of 0.25" = 35 AU), obtained with the IRAM Plateau de Bure interferometer and supplemented by slightly lower resolution observations from the Submillimeter Array. We fit these data with simple morphological models to characterize the spectacular ring-like emission structure of this disk...
Downloads: 7
[texts]1899 hardy perennials from seed : general offer of hardy cacti, Colorado wild flowers, novelties in plants and seeds (Volume 1899) - D.M. Andrews (Firm)
Cover title
Keywords: Nurseries (Horticulture) Colorado Boulder Catalogs; Nursery stock Colorado Boulder Catalogs; Flowers Seeds Catalogs; Cactus Catalogs; Wild flowers Catalogs; Shrubs Catalogs; Conifers Catalogs
[texts]Submillimeter Observations of the Young Low-Mass Object IRAS 04158+2805 - Sean M. Andrews
We present high spatial resolution Submillimeter Array observations and supplementary single-dish photometry of the molecular gas and dust around IRAS 04158+2805, a young source with spectral type M5-M6 in the Taurus star-forming region. A bright, highly elongated dust structure that extends 8" (~1120 AU) in diameter is revealed in a 883 micron thermal continuum image. This emission geometry is in good agreement with optical observations that show a similar structure in absorption, aligned perpe...
Downloads: 1
[texts]A Resolved Millimeter Emission Belt in the AU Mic Debris Disk - David J. Wilner
We present imaging observations at 1.3 millimeters of the debris disk surrounding the nearby M-type flare star AU Mic with beam size 3 arcsec (30 AU) from the Submillimeter Array. These data reveal a belt of thermal dust emission surrounding the star with the same edge-on geometry as the more extended scattered light disk detected at optical wavelengths. Simple modeling indicates a central radius of ~35 AU for the emission belt...
Downloads: 17
[texts]X-Ray and Infrared Observations of Embedded Young Stars in L1630 - T. Simon
The HH 24-26 star-forming region within the L1630 dark cloud in Orion contains a remarkable collection of rare Class 0 and Class I protostars, collimated molecular and ionized jets, and a luminous but spatially unresolved ASCA X-ray source. To study the X-ray properties of the embedded protostar population of that region, we have obtained a deep X-ray image with the ACIS-S camera on board the Chandra X-Ray Observatory...
Downloads: 5
[texts]A Disk-based Dynamical Mass Estimate for the Young Binary V4046 Sgr - Katherine A. Rosenfeld
We present sensitive, arcsecond-resolution Submillimeter Array observations of the 12CO J=2-1 line emission from the circumstellar disk orbiting the double-lined spectroscopic binary star V4046 Sgr. Based on a simple model of the disk structure, we use a novel Monte Carlo Markov Chain technique to extract the Keplerian velocity field of the disk from these data and estimate the total mass of the central binary...
Downloads: 4
[texts]Protoplanetary Disk Structures in Ophiuchus - Sean M. Andrews
We present a high angular resolution (0.3" = 40 AU) SMA survey of the 870 micron thermal continuum emission from 9 of the brightest, and therefore most massive, circumstellar disks in the ~1 Myr-old Ophiuchus star-forming region. Using 2-D radiative transfer calculations, we simultaneously fit the observed continuum visibilities and broadband spectral energy distribution for each disk with a parametric structure model...
Downloads: 3
[texts]The Structure of the DoAr 25 Circumstellar Disk - Sean M. Andrews
We present high spatial resolution (< 0.3" = 40$ AU) Submillimeter Array observations of the 865 micron continuum emission from the circumstellar disk around the young star DoAr 25. Despite its bright millimeter emission, this source exhibits only a comparatively small infrared excess and low accretion rate, suggesting that the material and structural properties of the inner disk may be in an advanced state of evolution...
Downloads: 7
[texts]Special trade list of rare seeds of Colorado plants, shrubs, etc. : and price list of hardy cacti (Volume 1900) - D.M. Andrews (Firm)

Keywords: Nursery stock, Colorado, Boulder, Catalogs; Flowers, Seeds, Catalogs; Cactus, Catalogs; Shrubs, Catalogs
Downloads: 1
[texts]1900 catalogue of plants and seeds of rare flowers : comprising hardy cacti, select hardy perennials, Colorado shrubs, bulbs, alpines, etc. (Volume 1900) - D.M. Andrews (Firm)

Keywords: Nursery stock Colorado Boulder Catalogs; Flowers Seeds Catalogs; Cactus Catalogs; Wild flowers Catalogs; Shrubs Catalogs; Conifers Catalogs
Downloads: 1
[texts]Descriptions and prices of one hundred select hardy perennial plants of the Rocky Mountains (Volume 1897) - D.M. Andrews (Firm)
Cover title
Keywords: Nurseries (Horticulture) Colorado Boulder Catalogs; Nursery stock Colorado Boulder Catalogs; Flowers Seeds Colorado Boulder Catalogs; Cactus Colorado Boulder Catalogs; Wild flowers Colorado Boulder Catalogs; Shrubs Colorado Boulder Catalogs; Conifer
Downloads: 2
[texts]Catalogue 8A : rare seeds of the Rocky Mountains and Western U.S. (Volume 1898) - D.M. Andrews (Firm)
Cover title
Keywords: Nursery stock, Colorado, Boulder, Catalogs; Flowers, Seeds, Catalogs; Cactus, Catalogs; Shrubs, Catalogs; Conifers, Catalogs
Downloads: 3
[texts]Resolving the CO Snow Line in the Disk around HD 163296 - Chunhua Qi
We report Submillimeter Array (SMA) observations of CO (J=2--1, 3--2 and 6--5) and its isotopologues (13CO J=2--1, C18O J=2--1 and C17O J=3--2) in the disk around the Herbig Ae star HD 163296 at ~2" (250 AU) resolution, and interpret these data in the framework of a model that constrains the radial and vertical location of the line emission regions. First, we develop a physically self-consistent accretion disk model with an exponentially tapered edge that matches the spectral energy distribution...
Downloads: 7
[texts]Stringent Limits on the Polarized Submillimeter Emission from Protoplanetary Disks - A. Meredith Hughes
We present arcsecond-resolution Submillimeter Array (SMA) polarimetric observations of the 880 um continuum emission from the protoplanetary disks around two nearby stars, HD 163296 and TW Hydrae. Although previous observations and theoretical work have suggested that a 2-3% polarization fraction should be common for the millimeter continuum emission from such disks, we detect no polarized continuum emission above a 3-sigma upper limit of 7 mJy in each arcsecond-scale beam, or
Downloads: 5
[texts]Disk Imaging Survey of Chemistry with SMA: II. Southern Sky Protoplanetary Disk Data and Full Sample Statistics - Karin I. Oberg
This is the second in a series of papers based on data from DISCS, a Submillimeter Array observing program aimed at spatially and spectrally resolving the chemical composition of 12 protoplanetary disks. We present data on six Southern sky sources - IM Lup, SAO 206462 (HD 135344b), HD 142527, AS 209, AS 205 and V4046 Sgr - which complement the six sources in the Taurus star forming region reported previously...
Downloads: 12
[texts]Disk Imaging Survey of Chemistry with SMA (DISCS): I. Taurus Protoplanetary Disk Data - Karin I. Oberg
Chemistry plays an important role in the structure and evolution of protoplanetary disks, with implications for the composition of comets and planets. This is the first of a series of papers based on data from DISCS, a Submillimeter Array survey of the chemical composition of protoplanetary disks. The six Taurus sources in the program (DM Tau, AA Tau, LkCa 15, GM Aur, CQ Tau and MWC 480) range in stellar spectral type from M1 to A4 and offer an opportunity to test the effects of stellar luminosi...
Downloads: 14
[texts]Resolved Submillimeter Observations of the HR 8799 and HD 107146 Debris Disks - A. Meredith Hughes
We present 880 um Submillimeter Array observations of the debris disks around the young solar analogue HD 107146 and the multiple-planet host star HR 8799, at an angular resolution of 3" and 6", respectively. We spatially resolve the inner edge of the disk around HR 8799 for the first time. While the data are not sensitive enough (with rms noise of 1 mJy) to constrain the system geometry, we demonstrate that a model by Su et al...
Downloads: 4
[texts]A Spatially Resolved Inner Hole in the Disk around GM Aurigae - A. Meredith Hughes
We present 0.3 arcsec resolution observations of the disk around GM Aurigae with the Submillimeter Array (SMA) at a wavelength of 860 um and with the Plateau de Bure Interferometer at a wavelength of 1.3 mm. These observations probe the distribution of disk material on spatial scales commensurate with the size of the inner hole predicted by models of the spectral energy distribution. The data clearly indicate a sharp decrease in millimeter optical depth at the disk center, consistent with a defi...
Downloads: 5
[texts]Structure and Composition of Two Transitional Circumstellar Disks in Corona Australis - A. M. Hughes
The late stages of evolution of the primordial circumstellar disks surrounding young stars are poorly understood, yet vital to constrain theories of planet formation. We consider basic structural models for the disks around two ~10 Myr-old members of the nearby RCrA association, RX J1842.9-3532 and RX J1852.3-3700. We present new arcsecond-resolution maps of their 230 GHz continuum emission from the Submillimeter Array and unresolved CO(3-2) spectra from the Atacama Submillimeter Telescope Exper...
Downloads: 13
[texts]An Old Disk That Can Still Form a Planetary System - Edwin A. Bergin
From the masses of planets orbiting our Sun, and relative elemental abundances, it is estimated that at birth our Solar System required a minimum disk mass of ~0.01 solar masses within ~100 AU of the star. The main constituent, gaseous molecular hydrogen, does not emit from the disk mass reservoir, so the most common measure of the disk mass is dust thermal emission and lines of gaseous carbon monoxide...
Downloads: 4
[texts]The TW Hya Disk at 870 microns: Comparison of CO and Dust Radial Structures - Sean M. Andrews
We present high resolution (0.3" = 16 AU), high signal-to-noise ratio Submillimeter Array observations of the 870 microns (345 GHz) continuum and CO J=3--2 line emission from the protoplanetary disk around TW Hya. Using continuum and line radiative transfer calculations, those data and the multiwavelength spectral energy distribution are analyzed together in the context of simple two-dimensional parametric disk structure models...
Downloads: 2
[texts]Confirming the Primarily Smooth Structure of the Vega Debris Disk at Millimeter Wavelengths - A. M. Hughes
Clumpy structure in the debris disk around Vega has been previously reported at millimeter wavelengths and attributed to concentrations of dust grains trapped in resonances with an unseen planet. However, recent imaging at similar wavelengths with higher sensitivity has disputed the observed structure. We present three new millimeter-wavelength observations that help to resolve the puzzling and contradictory observations...
Downloads: 16
[texts]Millimeter Emission Structure in the first ALMA Image of the AU Mic Debris Disk - Meredith A. MacGregor
We present 1.3 millimeter ALMA Cycle 0 observations of the edge-on debris disk around the nearby, ~10 Myr-old, M-type star AU Mic. These observations obtain 0.6 arcsec (6 AU) resolution and reveal two distinct emission components: (1) the previously known dust belt that extends to a radius of 40 AU, and (2) a newly recognized central peak that remains unresolved. The cold dust belt of mass about 1 lunar mass is resolved in the radial direction with a rising emission profile that peaks sharply at...
Downloads: 1
[texts]Constraints on the Radial Variation of Grain Growth in the AS 209 Circumstellar Disk - Laura M. Pérez
We present dust continuum observations of the protoplanetary disk surrounding the pre-main sequence star AS 209, spanning more than an order of magnitude in wavelength from 0.88 to 9.8 mm. The disk was observed with sub-arcsecond angular resolution (0.2"-0.5") to investigate radial variations in its dust properties. At longer wavelengths, the disk emission structure is notably more compact, providing model-independent evidence for changes in the grain properties across the disk...
Downloads: 2
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